KRISTIE RIEKEN, AP Sports WriterHOUSTON (AP) — Case Keenum will start at quarterback for the Houston Texans on Sunday at unbeaten Kansas City.Coach Gary Kubiak says Matt Schaub, who is dealing with injuries to his right ankle and foot, won't play this week.Keenum was a record-setting quarterback at the University of Houston before spending last season on the practice squad. The undrafted free agent has never appeared in a regular-season NFL game.The Texans (2-4) have lost four straight games, hurt by penalties, turnovers and other mistakes. Kubiak chose to go with Keenum over backup T.J. Yates, who led Houston to its first playoff win two years ago when Schaub was hurt. He struggled Sunday after Schaub was hurt, throwing two interceptions.

KANSAS CITY, Mo. (AP) — Every time Chiefs quarterback Alex Smith is flushed from the pocket, it seems that one of two things happens: He uses his fleet feet to scramble for yards, or he throws the ball away.

Neither of which is a bad thing.

The Chiefs have never had a quarterback who can make things happen on the ground with the same nimbleness as Smith, nor have they had one in recent years who is smart enough to throw the ball into the third row of seats rather than take a sack or force a pass into coverage.

"Listen, he's taking care of the football, and when it counts, he makes the plays. I appreciate that," Chiefs coach Andy Reid said. "We're winning football games and he's doing a nice job of managing it, and everyone feeds off it, both sides of the ball, his ability to manage it."

The Chiefs knew they weren't getting Peyton Manning or Tom Brady when they shipped a pair of draft picks to the 49ers to acquire Smith in the offseason. But they also knew they were getting a quarterback who would value possessions and minimize mistakes.

In short, they wanted a quarterback who was selfless.

Smith is only under contract through next season. It would behoove him to start putting up the kind of gaudy statistics that might earn him a lucrative new contract.

Instead, he's content to throw the ball away at the expense of his own completion percentage, which is at its worst in six years. Or accept check-downs and dump-offs at the expense of his yards per attempt, which likewise is its worst since a forgettable 2007 season in San Francisco.

"There are times when a guy comes clean and he has to sail it away, because the timing of the route has been disrupted. He's done a nice job of that," said Chiefs offensive coordinator Doug Pederson, a former quarterback. "I know it reflects on a quarterback's completion percentage a little bit, but that's part of the game, and then you come back and get them on the next play."

Even his completion percentage doesn't mean a whole lot to Smith, though.

"I mean, that statistic, it's not something I'm directly looking at. It's what throws should I have made? What decisions should I have made differently?" he explained. "You look at things on a play-by-play basis. Could I make a better decision? Could I make a better throw?"

In some cases, the answer is a resounding yes.

Several times he's missed an open receiver downfield, calling into question his ability to throw the deep ball. He's also struggled to get the ball to wide receiver Dwayne Bowe, who has just 20 catches after signing a $56 million, five-year deal in the offseason.

Page 2 of 2 - But there are a lot more reasons for those shortcomings than Smith not doing his job. Bowe has received the majority of defensive attention this season, and an offensive line that features a rookie right tackle in Eric Fisher has had difficulty giving Smith time to scan the field.

"Alex has a big arm, he controls the offense and he makes plays when he has to," Bowe said. "If I'm taking two people, he's going to get the check-down. We're going to play conservative. We're not going to make mistakes."

So far, that approach has been working. The Chiefs (6-0) lead the NFL at plus-12 in turnover differential, one year after tying Philadelphia at a league-worst minus-24.

A big reason for that: Smith has thrown just three interceptions. Only the Broncos' Peyton Manning has thrown fewer picks while attempting more passes.

"I've always been impressed by Alex," said Texans coach Gary Kubiak, whose team faces Kansas City on Sunday, and who'd no doubt love to have a quarterback valuing possessions right now.

"He's brilliant, smart," Kubiak said. "I had a chance to visit with him when he was coming out. I think he fits exactly what Andy wants to do. He has the opportunity to make plays with his feet when things break down. I've always been a fan."

So is Reid, who tried to acquire Smith when he was coaching the Eagles.

"He's got things he needs to keep working on. The thing that's most important right now is he continues to get reps with his receivers around him," Reid said. "You've got to be sharp and on the same page with one another, and they're working through all of that."